I knew a guy who used to work for microsoft game studios or something and he was able to mess around with the game types kinda like that. He didnt quite go that extreme though. He added little funny things to the game that displayed differently to each person. It would have your gamertag for example in the game type and it would say lets hump(insertyourgamertag) and it would have control sticks moving up and down. That was a long as time ago so im sure he has probably become alot more creative with it now.